scholarly journals Modeling of Flexible Bodies for the Study of Control in the Simulink Environment

2020 ◽  
Vol 10 (17) ◽  
pp. 5861
Author(s):  
Laura Salamina ◽  
Daniele Botto ◽  
Stefano Mauro ◽  
Stefano Pastorelli
Keyword(s):  
Optimal Solution ◽  
Rigid Bodies ◽  
Machining Process ◽  
Fe Model ◽  
Matlab Simulation ◽  
Mechatronic Systems ◽  
Simulation Code ◽  
Flexible Bodies ◽  
Stiffness Matrices ◽  
Integrate Control

When studying complex mechatronic systems, it is useful to build models able to simulate both the dynamics of the phenomenon and the control system applied. Typically, the bodies involved are modeled as rigid bodies. In this work, a technique for modeling flexible bodies in Simulink environment is presented. Simulink is a powerful instrument where it is quite easy to integrate control algorithms with complex systems. The solution developed is presented and applied to a machining center. Modern machining centers ensure a level of accuracy that traditional manual machines cannot reach. Simulations of the working process considering vibrations are needed to obtain high precision machining. These simulations aim to determine the error in the position of the tool and to help designers in finding the optimal solution in terms of machining velocity and precision. This work is focused on the carriage of a machine tool moving along horizontal guides, typically named Z-axis. The axis is actuated and borne by a linear motor; therefore, movable constraints must be modeled. A finite-element (FE) model of the carriage was reduced with a Craig-Bampton reduction to provide the mass and stiffness matrices for an in-house Matlab simulation code. The rigid constraints of the carriage were implemented in the model as moving stiffnesses, and their value was set to obtain continuity of the constraints in the discrete model. In the end, a map of different vibrational configurations is proposed to visualize the possible errors that a machining process can generate.

Effects of countersunk hole geometry errors on the fatigue performance of CFRP bolted joints

2021 ◽  
pp. 095440542110285
Author(s):  
Xuda Qin ◽  
Xingfeng Cao ◽  
Hao Li ◽  
Meng Zhou ◽  
Ende Ge ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Bolted Joints ◽  
Fatigue Performance ◽  
Machining Process ◽  
Fe Model ◽  
Hole Making ◽  
Hole Geometry ◽  
Geometry Error ◽  
The Relationship ◽  
Hole Machining

Due to good aerodynamic performance and reliability, countersunk bolt joint is one of the most commonly used connection methods for carbon fiber reinforced polymer (CFRP) components in the aircraft. However, the countersunk hole machining process is inevitably accompanied by geometric errors, which will directly affect the mechanical properties of the joint structure. This paper presents a numerical and experimental investigation on the effect of countersunk hole geometry errors on the fatigue performance of CFRP bolted joints. FE model of CFRP countersunk bolted joints with designed geometry errors are established, and the rationality of the FE analysis was verified by fatigue life and failure forms. The CFRP bolted structure failure mechanism under fatigue load and influence of hole-making geometry error (including countersunk fillets radius, countersunk depth, and countersunk angle) on the fatigue life are investigated. Based on the relationship between fatigue life and the geometry error, the corresponding tolerances for CFRP bolt joint countersunk hole are determined as well. The research results can provide a reference for establishing reasonable geometric accuracy requirements for CFRP joint hole machining.

Failure mechanics analysis of AISI 4340 steel using finite element modeling of the milling process

2021 ◽  
pp. 030932472110580
Author(s):  
Muhammed Muaz ◽  
Sanan H Khan
Keyword(s):  
Finite Element ◽  
Failure Analysis ◽  
End Milling ◽  
Physical Phenomenon ◽  
Machining Process ◽  
Fe Model ◽  
Dissipation Energy ◽  
Damage Initiation ◽  
Milling Operation ◽  
Cutting Operation

A slot cutting operation is studied in this paper using a rotating/translating flat end milling insert. Milling operation usually comprises up-milling and down-milling processes. These two types of processes have different behaviors with opposite trends of the forces thus making the operation complex in nature. A detailed Finite Element (FE) model is proposed in this paper for the failure analysis of milling operation by incorporating damage initiation criterion followed by damage evolution mechanism. The FE model was validated with experimental results and good correlations were found between the two. The failure criteria field variable (JCCRT) was traced on the workpiece to observe the amount and rate of cutting during the machining process. It was found that the model was able to predict different failure energies that are dissipated during the machining operation which are finally shown to be balanced. It was also shown that the variation of these energies with the tool rotation angle was following the actual physical phenomenon that occurred during the cutting operation. Among all the energies, plastic dissipation energy was found to be the major contributor to the total energy of the system. A progressive failure analysis was further carried out to observe the nature of failure and the variation of stress components and temperature occurring during the machining process. The model proposed in this study will be useful for designers and engineers to plan their troubleshooting in various applications involving on-spot machining.

A fast and accurate solution to optimal design of eddy-current PMCs with standard disc type

2021 ◽  
pp. 1-19
Author(s):  
Zheng rong Xia ◽  
Yong chen Pei ◽  
Dong xu Wang ◽  
Shun Wang
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Optimal Solution ◽  
Industrial Applications ◽  
Accurate Solution ◽  
Parameter Determination ◽  
Experimental Investigations ◽  
Fe Model ◽  
Contribution Rate ◽  
Standard Disc

Although permanent magnet couplings (PMCs) have been under research for many years and have found successful industrial applications, this is still a technology under development. Accurate parameter determination is of significance for performance analysis and critical decisions on PMC design. However, the determination can often lead to an unacceptable increase in computation, especially when finite elements (FE) are used. The study aims to develop an FE model that is used for the structural design of a standard-disc type PMC for optimal torque. For the quick and accurate design, an integration optimal solution of the response surface methodology (RSM) and the Taguchi’s method was proposed. To verify the simulation, a series of experimental investigations were conducted on a self-developed testing platform. Furthermore, for a minimum set of FE analyses (FEA), a quantitative indicator called contribution rate, which can reflect effect level of structure parameters on the torque, was given based on the Taguchi method. Apart from this, the orthogonal matrix was used for the reduction of the FE calculation. Based on the contribution rate, the response surface methodology was adopted for the optimal torque determination with no increase in the PM volume. According to the optimization results, a fitting formula, which considers the contribution rates of the optimization variables, was presented. The results suggest that the FE simulations agree very well with the experiments, and the fitting formula can be used in the PMC design.

Optimal Parameter Design in Flip Chip Micro-Machining Process for Solder Residue by Using Design of Experiments Approach

2010 ◽  
Vol 126-128 ◽  
pp. 867-872
Author(s):  
Jian Long Kuo ◽  
Chun Cheng Kuo
Keyword(s):  
Design Of Experiments ◽  
Manufacturing Process ◽  
Semiconductor Manufacturing ◽  
Flip Chip ◽  
Optimal Parameter ◽  
Optimal Solution ◽  
Machining Process ◽  
Passive Component ◽  
Quality Properties ◽  
Chip Quality

Since the solder residue is essential in the semiconductor manufacturing process, it has great impact on the flip chip quality considerably. This paper intends to improve the flip chip quality and try to obtain an optimal solution for the system parameters in the flip chip manufacturing process. The SMT manufacturing process is studied for discussion. The amount of solder and the size of solder are selected as the two quality properties. During the flux cleaning process, many solders are left on the passive component side. The balling might flow into the chip. It will cause the bump short in the chip which will affect the quality of the flip chip severely. In this paper, response surface method is adopted as the design of experiments. The objective function and subjective constrained conditions are defined to formulate the optimization problem. The confirmation experimental results are also provided to prove the validity. It is believed that the optimization results are helpful to the improvement of the semiconductor manufacturing process.

Influence of Flexible Bodies in Military Tracked Vehicle Dynamics

2016 ◽  
Vol 8 (2) ◽  
Author(s):  
S. Jothi ◽  
V. Balamurugan ◽  
K.M. Mohan
Keyword(s):  
Dynamic Simulation ◽  
Rigid Bodies ◽  
The Finite Element Method ◽  
Tracked Vehicle ◽  
Finite Element Method Result ◽  
Flexible Bodies ◽  
Tracked Vehicles ◽  
Dynamic Studies ◽  
The Military ◽  
Test Result

Tracked vehicles are meant to be used in the harsh cross country environment. In particular, the military tracked vehicles are highly exposed to severe terrains and critical handling conditions. Yet while carrying out the dynamic studies, the tracked vehicles, in general, are modeled as rigid bodies. Hence in this article, an attempt has been made to understand closely the dynamics of a tracked vehicle with the inclusion of some parts of the tracked vehicle viz., hull side plates and road wheel arms, as flexible bodies in the dynamic analysis using the finite element method. Result of the flexible dynamic simulation is also compared with the tracked vehicle analysis with the same parts modeled as rigid bodies. In this investigation, dimensions of the standard staggered trapezoidal blocks terrain meant for testing the tracked vehicles is used to carry out the dynamic studies on the tracked vehicle. The dynamic simulation result of the flexible tracked vehicle model is also compared with the experimental test result of the actual tracked vehicle conducted in the actual trapezoidal blocks terrain.

scholarly journals Survey of Mechatronic Techniques in Modern Machine Design

2012 ◽  
Vol 2012 ◽  
pp. 1-9
Author(s):  
Devdas Shetty ◽  
Lou Manzione ◽  
Ahad Ali
Keyword(s):  
Design Process ◽  
Machining Process ◽  
Frame Structure ◽  
Automated System ◽  
Product Development Process ◽  
Mechatronic Systems ◽  
Adaptive Controls ◽  
Feed Drives ◽  
Simulation Based ◽  
Smart Machine

Increasing demands on the productivity of complex systems, such as manufacturing machines and their steadily growing technological importance will require the application of new methods in the product development process. A smart machine can make decisions about the process in real-time with plenty of adaptive controls. This paper shows the simulation based mechatronic model of a complex system with a better understanding of the dynamic behavior and interactions of the components. This offers improved possibilities of evaluating and optimizing the dynamic motion performance of the entire automated system in the early stages of the design process. Another effect is the growing influence of interactions between machine components on achievable machine dynamics and precision and quality of components. The examples cited in this paper, demonstrate the distinguishing feature of mechatronic systems through intensive integration. The case studies also show that it will no longer be sufficient to focus solely on the optimization of subsystems. Instead it will be necessary to strive for optimization of the complete system. The interactions between machine components, the influence of the control system and the machining process will have to be considered during the design process and the coordination of feed drives and frame structure components.

Output-Only Modal Analysis of an Internal Unreachable Module Embedded in a Space Electronic Equipment

2012 ◽  
Author(s):  
Lassaad Ben Fekih ◽  
Georges Kouroussis ◽  
David Wattiaux ◽  
Olivier Verlinden ◽  
Christophe De Fruytier
Keyword(s):  
Finite Element ◽  
Modal Analysis ◽  
Degrees Of Freedom ◽  
Transverse Direction ◽  
Mode Shapes ◽  
Fe Model ◽  
Fe Method ◽  
Numeric Model ◽  
Stiffness Matrices ◽  
Output Only

An approach is proposed to identify the modal properties of a subsystem made up of an arbitrary chosen inner module of embedded space equipment. An experimental modal analysis was carried out along the equipment transverse direction with references taken onto its outer housing. In parallel, a numerical model using the finite element (FE) method was developed to correlate with the measured results. A static Guyan reduction has led to a set of master degrees of freedom in which the experimental mode shapes were expanded. An updating technique consisting in minimizing the dynamic residual induced by the FE model and the measurements has been investigated. A last verification has consisted in solving the numeric model composed of the new mass and stiffness matrices obtained by means of a minimization of the error in the constitutive equation method.

Simulation and Optimization of an Adjustable Inlet Guide Vane for Industrial Turbo Compressors

2008 ◽  
Author(s):  
Michael Hensges
Keyword(s):  
Guide Vane ◽  
Rigid Bodies ◽  
Inlet Guide Vane ◽  
Fe Model ◽  
Fe Method ◽  
Friction Forces ◽  
Simulation And Optimization ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Joint Reaction

To investigate the kinematics and dynamics of an adjustable inlet guide vane mechanism (IGV) for industrial turbo compressors, an IGV was modeled as a multibody system (MBS) consisting of elastic interconnections and rigid bodies. Besides investigating the IGV kinematics, its vibrations and structural strength were also verified numerically. The kinematic analyses enabled the design to be optimized in terms of undesirable collisions between the interconnected bodies. The pressure exerted on the guide vanes, which is calculated by CFD simulations, forms a set of forces and torques for each blade. These sets were created for two different performance maps, referred to in the following as Gas I and Gas II. Calculating the desired drive torque, joint reaction forces and the driving ring’s displacements were the essential inputs for the dynamic multibody analyses performed. These investigations showed that the desired torque to drive the mechanism is governed by the sliding element’s friction forces. The gas forces were able to raise the torque by roughly 6% and 32.6% for Gas I and II, respectively. Due to uncertainties in the determination of the friction coefficients, the highest expected values were taken into account for selecting an accurate actuator for the IGV. The strength and vibration analyses were carried out using the Finite Element (FE) Method. All computed critical natural frequencies of the IGV can be empirically considered to be highly damped resonances in the actual system due to joint friction effects. Reaction forces determined by the dynamic multibody analyses were transferred as loads to the FE model. In most cases, the joint reaction forces have been so low that no further investigations were necessary. Hence, verification of strength was carried out using a contact FE analysis for the highest loading condition between the assembly and the pin, which transfers the entire drive force from a lever into the driving ring.

scholarly journals Defect Removal and Rearrangement of Wood Board Based on Genetic Algorithm

Forests ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 26
Author(s):  
Yutu Yang ◽  
Zilong Zhuang ◽  
Yabin Yu
Keyword(s):  
Genetic Algorithm ◽  
Large Scale ◽  
Great Influence ◽  
Optimal Solution ◽  
Solid Wood ◽  
Raw Material ◽  
Machining Process ◽  
Utilization Rate ◽  
Standard Size ◽  
Wood Board

Defects on a solid wood board have a great influence on the aesthetics and mechanical properties of the board. After removing the defects, the board is no longer the standard size; manual drawing lines and cutting procedure is time-consuming and laborious; and an optimal solution is not necessarily obtained. Intelligent cutting of the board can be realized using a genetic algorithm. However, the global optimal solution of the whole machining process cannot be obtained by separately considering the sawing and splicing of raw materials. The integrated consideration of wood board cutting and board splicing can improve the utilization rate of the solid wood board. The effective utilization rate of the board with isolated consideration of raw material sawing with standardized dimensions of wood pieces and board splicing is 79.1%, while the shortcut splicing optimization with non-standardized dimensions for the final board has a utilization rate of 88.6% (which improves the utilization rate by 9.5%). In large-scale planning, the use of shortcut splicing optimization also increased the utilization rate by 12.14%. This has certain guiding significance for actual production.

Real-Time Explicit Flexible Multibody Dynamics Solver With Application to Virtual-Reality Based E-Learning

2011 ◽  
Author(s):  
Tamer M. Wasfy ◽  
Hatem M. Wasfy ◽  
Jeanne M. Peters
Keyword(s):  
Virtual Reality ◽  
Finite Elements ◽  
Rigid Body ◽  
Real Time ◽  
Multibody Dynamics ◽  
Flexible Multibody Dynamics ◽  
Rigid Bodies ◽  
Flexible Bodies ◽  
Joint Contact ◽  
E Learning

A flexible multibody dynamics explicit time-integration parallel solver suitable for real-time virtual-reality applications is presented. The hierarchical “scene-graph” representation of the model used for display and user-interaction with the model is also used in the solver. The multibody system includes rigid bodies, flexible bodies, joints, frictional contact constraints, actuators and prescribed motion constraints. The rigid bodies rotational equations of motion are written in a body-fixed frame with the total rigid body rotation matrix updated each time step using incremental rotations. Flexible bodies are modeled using total-Lagrangian spring, truss, beam and hexahedral finite elements. The motion of the elements is referred to a global inertial Cartesian reference frame. A penalty technique is used to impose joint/contact constraints. An asperity-based friction model is used to model joint/contact friction. A bounding box binary tree contact search algorithm is used to allow fast contact detection between finite elements and other elements as well as general triangular/quadrilateral rigid-body surfaces. The real-time solver is used to model virtual-reality based experiments (including mass-spring systems, pendulums, pulley-rope-mass systems, billiards, air-hockey and a solar system) for a freshman university physics e-learning course.

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